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•Ionic Liquids favor the production of acid formic and methanol from CO2 hydrogenation.•Ionic Liquids improve product yields to ~ 65% for formic acid and ~ 68% for methanol.•CO2 ...hydrogenation occurs at ambient temperature and low pressure conditions.•Methanol is produced with less stoichiometric hydrogen requirement.
Direct hydrogenation of carbon dioxide (CO2) to formic acid is unfavorable thermodynamically, which makes its production limited. In this study, a thermodynamic analysis of CO2 hydrogenation to binary product systems of methanol and formic acid promoted by ionic liquid (IL) (1-ethyl-2,3-dimethylimidazolium nitrite, (EdmimNO2) is presented. The analysis is conducted in Aspen Plus using the Gibbs energy minimization approach combined with a vapor–liquid equilibrium (VLE) for the solvation of CO2 in IL. It is demonstrated that solvating CO2 in ILs is an attractive alternative to overcome the thermodynamic difficulty associated with the product yield, especially formic acid. The EdmimNO2 promoted system is very effective for the simultaneous production of formic acid and methanol at 25 °C and 17 bar with a yield of 35% formic acid and 30% methanol at a CO2/H2/IL ratio of 1/2/2. The results show a marked improvement in the yield of formic acid to other previously conducted studies on formic acid production.
The use of thermal power plants has been increasing lately, despite its use being associated with high greenhouse gases emissions, especially carbon dioxide. In the context of the Paris Agreement of ...2015, carbon dioxide capture, storage and utilization techniques must be increasingly employed to reduce environmental impacts. The utilization of carbon dioxide from a power plant flue gas as feedstock to other chemicals synthesis (such as ammonia and urea) arises as a good alternative to achieve near-zero carbon dioxide emissions. The aim of this work is to propose an alternative route, based on the bi-reforming of methane, for the synthesis gas section of ammonia and urea production plants, in order to promote carbon dioxide abatement, comparing this innovative route with the conventional and century-long existing process. Technical and environmental metrics of the proposed and conventional routes were compared. Aspen Plus® process simulator was used to simulate the bi-reforming process and both routes for ammonia and urea synthesis and choose the operational parameters. Simulation results show that for a target production of 2000 tonne/day of urea, the proposed alternative route has the potential to abate 745 tonne/day of carbon dioxide, while the conventional route emits 1156 tonne/day of carbon dioxide. Comparison of technical metrics of both routes shows that the proposed route requires an electricity usage of 0.27 MWh/tonne of products while the conventional route requires 0.47 MWh/tonne of products. However, hydrogen yield in the conventional route is higher than in its counterpart, with 0.41 and 0.22 tonnes of hydrogen produced for each tonne of inlet natural gas in the conventional and proposed routes, respectively. Comparison of economic metrics of both configurations show that none of the routes are economically viable, however, the alternative route has better economic indicators besides successfully promotes carbon dioxide abatement.
•The feasibility of integrating of methane bi-reforming and ammonia processes is evaluated.•Bi-reforming can replace conventional steam reforming and partial oxidation in the ammonia process.•The innovative route presents better economic results.•The proposed route successfully promotes carbon dioxide abatement.
Context
The conversion of carbon dioxide (CO
2
) to formic acid (FA) through hydrogenation using 1-ethyl-2,3- dimethyl imidazolium nitrite (EDIN) ionic liquid was studied to understand the catalytic ...roles within EDIN. CO
2
hydrogenation in various solvents has been explored, but achieving high efficiency and selectivity remains challenging due to the thermodynamic stability and kinetic inertness of CO
2
. This study explored two mechanistic pathways through theoretical calculations, revealing that the nitrite (NO
2
−
) group is the most active site. The oxygen site on nitrite favorably activates H2, while the nitrogen site shows a minor activation barrier of 108.90 kJ/mol. The Gibbs energy variation indicates stable FA formation via EDIN, suggesting effective hydrogen (H
2
) activation and subsequent CO
2
conversion. These insights are crucial for developing improved catalytic sites and processes in ionic liquid catalysts for CO
2
hydrogenation.
Methods
Quantum chemical calculations were conducted using the ORCA software package at the Restricted Hartree-Fock (RHF) and density functional theory (DFT) levels. The RHF method, known for its predictive abilities in simpler systems, provided a baseline description of electronic structures. In contrast, DFT was employed for its effectiveness in complex interactions involving significant electron correlation. A valence triple-zeta polarization (def2-TZVPP) basis set was employed for both RHF and DFT, ensuring accurate and correlated calculations. The B3LYP functional was utilized for its rapid convergence and cost-efficiency in larger molecules. Dispersion corrected functionals (DFT-D) addressed significant dispersion forces in ionic liquids, incorporating Grimme’s D2, D3, and D4 corrections. Geometry optimizations, kinetics, and thermodynamic calculations were performed in the gas phase. The Nudged Elastic Band Transition State (NEB-TS) approach, combining Climbing Image-NEB (CINEB) and Eigenvector-Following (EF) methods, was used to find the minimum energy path (MEP) between reactants and products. Thermochemical analyses based on vibrational frequency calculations evaluated properties such as Enthalpy, Entropy, and Gibbs energy using ideal gas statistical mechanics.
The vgf gene has been identified as an energy homeostasis regulator. Vgf encodes a 617-aa precursor protein that is processed to yield an incompletely characterized panel of neuropeptides. Until now, ...it was an unproved assumption that VGF-derived peptides could regulate metabolism. Here, a VGF peptide designated TLQP-21 was identified in rat brain extracts by means of immunoprecipitation, microcapillary liquid chromatography-tandem MS, and database searching algorithms. Chronic intracerebroventricular (i.c.v.) injection of TLQP-21 (15 micrograms/day for 14 days) increased resting energy expenditure (EE) and rectal temperature in mice. These effects were paralleled by increased epinephrine and up-regulation of brown adipose tissue β2-AR (β2 adrenergic receptor) and white adipose tissue (WAT) PPAR-delta (peroxisome proliferator-activated receptor delta), β3-AR, and UCP1 (uncoupling protein 1) mRNAs and were independent of locomotor activity and thyroid hormones. Hypothalamic gene expression of orexigenic and anorexigenic neuropeptides was unchanged. Furthermore, in mice that were fed a high-fat diet for 14 days, TLQP-21 prevented the increase in body and WAT weight as well as hormonal changes that are associated with a high-fat regimen. Biochemical and molecular analyses suggest that TLQP-21 exerts its effects by stimulating autonomic activation of adrenal medulla and adipose tissues. In conclusion, we present here the identification in the CNS of a previously uncharacterized VGF-derived peptide and prove that its chronic i.c.v. infusion effected an increase in EE and limited the early phase of diet-induced obesity.
•Atmospheric chloride deposition is mapped in highly spatially variable conditions.•The effects of vegetation and distance from the coast are quantified.•The edge effect is a critical factor for ...accurate quantification.•Vegetation and coastal effects impact CMB-based groundwater recharge estimates.
Knowledge of atmospheric chloride deposition is a prerequisite for applying the chloride mass balance (CMB) method for groundwater recharge estimation. Compared to bare areas, vegetated areas can significantly enhance chloride deposition rates as the vegetation canopy provides a large surface onto which water droplets and aerosols settle. Although generally acknowledged, this effect has often been ignored in practical applications of the CMB method. This paper studies the variability of chloride deposition in a coastal basin characterised by a heterogeneous vegetation cover, and the implications of this variability for groundwater recharge estimation using observation wells in the saturated zone. The study area is located on the Eyre Peninsula in South Australia. The theory of the CMB method for groundwater recharge estimation is revised in the context of highly spatially variable chloride deposition. A GIS-based approach is developed for mapping the chloride deposition accounting for distance from the coast, distribution of vegetation and edge effects; the latter implying a lower chloride deposition inside a vegetation stand than at the edge. In order to quantify the significance of one or several of these effects for recharge estimation, different chloride deposition maps and corresponding recharge estimates are derived. Compared with the reference scenario that accounts for all effects, neglecting the coastal effect results in a 33–36% higher average recharge estimate, whereas neglecting the vegetation effect results in a 17–22% lower average recharge estimate. The latter numbers are likely to represent a lower bound of the impact of neglecting the vegetation effect. A critical factor for accurate determination of the influence of vegetation appears to be the edge effect, albeit its importance is subject to significant uncertainty that warrants further monitoring.
The use of fossil resources has lead to great increase in concentration of carbon dioxide (CO2) in the atmosphere beyond sustainable limits, which causes environmental issues such as greenhouse gas ...effect, climate change and extreme weather events and threats the human life. Thus, several researches have been focused on mitigate this problem. Possible strategies involve implementing technologies of carbon capture storage and utilization. Among them, integrated processes for carbon dioxide capture and its conversion into value-added products have gained attention. Carbon dioxide hydrogenation is among the most developed technologies for its conversion, but requires an external hydrogen (H2) source. Since the conversion of carbon dioxide is highly energy-demanding, assessing its overall process sustainability requires a comprehensive study on the whole system, including its raw material sources (carbon dioxide and hydrogen). Thus, this work proposes a multi-criteria framework to select suitable sources of carbon dioxide and hydrogen to be used in the conversion of carbon dioxide. Potential sources of carbon dioxide (from power plants to ethanol fermentation) and hydrogen (from dedicated production to by-product hydrogen) were evaluated considering environmental, economic, and technical aspects associated with the usage of each source. The Technique of Order Preference Similarity to the Ideal Solution (TOPSIS) is the multi-criteria decision analysis method used to aggregate the criteria and to rank each source individually and further in a pair-wise assessment to identify potential synergic combinations between carbon dioxide and hydrogen sources. Results suggested that using carbon dioxide from natural gas steam reforming, iron and steel industries, ethylene oxide and other high concentration point sources may be the ideal choice for sustainability. The analysis also indicated that hydrogen may be more sustainable if it is a process by-product or is produced by low-cost wind-powered electrolysis. It is important to consider that the analysis is based on several specific data inputs and assumptions, and that a lower score does not mean that the source is not worth investing in.
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•Using environmental, economic and technical indicators for hydrogen and carbon dioxide sources evaluation.•Multi-criteria decision analysis is used to assess the sustainability of individual sources and their combinations.•By-product hydrogen from steam crackers and coke oven gas showed good sustainability performance.•Using by-product hydrogen or wind-electrolysis with on-site/nearby available CO2 could result in a more sustainable process.
Recently, by whole exome sequencing of schizophrenia (SCZ) patients, we identified a subject that was homozygous for a novel missense substitution (c.391 A > G) in the glutamate acid decarboxylase 1 ...(GAD1) gene. GAD1 encodes for GAD67 enzyme, catalyzing the production of gamma-aminobutyric acid (GABA) from L-glutamic acid. Here, we studied the impact of this mutation on GAD67 activity, dimerization and subcellular localization. Biochemical assay revealed that c.391 A > G reduces GAD67 enzymatic activity by ~30%, probably due to the impaired homodimerization of homozygous mutants as highlighted by proximity ligation assays. The mutational screening of 120 genes of the "GABAergic system" in a cohort of 4,225 SCZ cases and 5,834 controls (dbGaP: phs000473.v1.p2), did not identify other cases that were homozygous for ultra-rare variants in GAD1, but highlighted an increased frequency of cases that were homozygous for rare variants in genes of the GABA system (SCZ: 0.14% vs. Controls: 0.00%; p-value = 0.0055). In conclusion, this study demonstrates the functional impact of c.391 A > G variant and its biological effect makes it a good candidate as risk variant for SCZ. This study also supports an involvement of ultra-rare variants in GABAergic genes in the etiopathogenesis of SCZ.
The clinical usefulness of two commercial peach extracts for SPT (by Lofarma SpA and ALK-Abellò, respectively) was compared in a multicenter study carried out in Italy. Peach allergic patients were ...tested with the two extracts in parallel and underwent the detection of IgE specific for all three peach allergens currently available (Pru p1, Pru p3, and Pru p4, respectively). The two extracts were almost identical in terms of sensitivity and specificity, being able to detect virtually all patients sensitized to stable peach allergens (lipid transfer protein (LTP) and, presumably, peamaclein) but scoring negative in patients exclusively sensitive to labile allergens (either PR-10 and/or profilin). Thus, the two extracts represent an excellent tool to carry out a preliminary component-resolved diagnosis of peach allergy at the first patient visit.
The relatively high spatial resolution, short revisit time and red-edge spectral band (705 nm) of the ESA Sentinel-2 Multi Spectral Imager makes this sensor attractive for monitoring water quality of ...coastal and inland waters. Reliable atmospheric correction is essential to support routine retrieval of optically active substance concentration from water-leaving reflectance. In this study, six publicly available atmospheric correction algorithms (Acolite, C2RCC, iCOR, l2gen, Polymer and Sen2Cor) are evaluated against above-water optical in situ measurements, within a robust methodology, in two optically diverse coastal regions (Baltic Sea, Western Channel) and from 13 inland waterbodies from 5 European countries with a range of optical properties. The total number of match-ups identified for each algorithm ranged from 1059 to 1668 with 521 match-ups common to all algorithms. These in situ and MSI match-ups were used to generate statistics describing the performance of each algorithm for each respective region and a combined dataset. All ACs tested showed high uncertainties, in many cases >100% in the red and >1000% in the near-infra red bands. Polymer and C2RCC achieved the lowest root mean square differences (~0.0016 sr−1) and mean absolute differences (~40–60% in blue/green bands) across the different datasets. Retrieval of blue-green and NIR-red band ratios indicate that further work on AC algorithms is required to reproduce the spectral shape in the red and NIR bands needed to accurately retrieve the chlorophyll-a concentration in turbid waters.
•A comparison of six algorithms for retrieving water leaving reflectance•Six publicly available atmospheric correction routines compared•Match-up dataset of 2 coastal environments and 13 inland waterbodies•Between 34 and 70 MSI granules per algorithm with match-ups
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